Vice President Mike Pence applauded the move by Trump, saying the president "continues to recruit smart and capable leaders focused on Making America Great Again." He added that Azar would bring "decades of health care experience" to his HHS post.

Congratulations to Alex Azar for being @POTUS' choice to lead @HHSGov. Alex brings decades of health care experience. @POTUS continues to recruit smart & capable leaders focused on Making America Great Again! https://t.co/2ZxGbIMp0n

Mr. Trump had indicated he might fire Price, and said he was "not happy" with the "optics" of the situation. Mr. Trump at the time called Price a "very fine person."

Politico first reported that Price had billed the government for at least $400,000 in private charter planes. A second report found that Price also used at least $500,000 worth of military jet travel abroad for him and his wife, Betty.

In his letter to the president, Price cited the recent controversies surrounding his expensive travel, saying "I have spent forty years both as a doctor and public servant putting people first. I regret that the recent events have created a distraction from these important objectives."

Price's tenure in the Trump administration lasted less than eight months.